Positioning of self-assembled InAs quantum dots by focused ion beam implantation
- Self-assembled quantum dots (QDs) are envisioned as building blocks for realization of novel nanoelectronic devices, for which the site-selective growth is highly desirable. This thesis presents a successful route toward selective positioning of self-assembled InAs QDs on patterned GaAs surface by combination of \(\textit {in situ}\) focused ion beam (FIB) implantation and molecular beam epitaxy (MBE) technology. First, a buffer layer of GaAs was grown by MBE before a square array of holes with a pitch of 1-2 \(\mu\)m was fabricated by FIB implantation of Ga and In, ions respectively. Later, an \(\textit {in-situ}\) annealing step followed by InAs deposition was performed. The InAs QDs were preferentially formed in the holes generated by FIB. The influence of ion dose, annealing parameters and InAs amount was investigated in this work. With optimized parameters, more than 50 % single dot occupancy per hole is achieved. Furthermore, the photoluminescence spectra from positioned QDs confirm their good optical quality.
Download full text files
Additional Services
| Author: | Minisha MehtaGND |
|---|---|
| URN: | urn:nbn:de:hbz:294-20921 |
| Referee: | Andreas D. WieckORCiDGND, Daniel HägeleGND |
| Document Type: | Doctoral Thesis |
| Language: | English |
| Date of Publication (online): | 2008/01/08 |
| Date of first Publication: | 2008/01/08 |
| Publishing Institution: | Ruhr-Universität Bochum, Universitätsbibliothek |
| Granting Institution: | Ruhr-Universität Bochum, Fakultät für Physik und Astronomie |
| Date of final exam: | 2007/12/10 |
| Creating Corporation: | Fakultät für Physik und Astronomie |
| GND-Keyword: | Ionenstrahl; Molekularstrahlopitaxie; Selbstorganisation; Quantenpunkt; Drei-Fünf-Halbleiter |
| Institutes/Facilities: | Lehrstuhl für angewandte Festkörperphysik |
| Dewey Decimal Classification: | Naturwissenschaften und Mathematik / Physik |
| faculties: | Fakultät für Physik und Astronomie |
| Licence (German): |  Keine Creative Commons Lizenz - es gelten der Veröffentlichungsvertrag und das deutsche Urheberrecht |
